1. Field of Invention
This invention generally relates to vesicular systems, specifically to a growth factor-sensitive vesicle.
2. Prior Art
Currently, conventional treatments for growth factor-overexpressing neoplasms are generally limited to surgery, radiation therapy, and generalized chemotherapy. Radiation therapy and generalized chemotherapy may result in significant side effects, including an increased risk of new tumor formation. Surgery, when feasible, is attendant with the risk of various surgical complications. Furthermore, combinations of treatments, usually radiation therapy and generalized chemotherapy, and recurring treatments, such as recurring radiation therapy, are often necessary, typically resulting in additional side effects and/or side effects of greater severity.
To achieve the goal of maximizing the effectiveness of chemotherapy while simultaneously minimizing undesirable systemic side effects, the ideal solution would be to use targeted drug delivery to release chemotherapeutic agents specifically in the neighborhood of growth factor-overexpressing neoplasms. Such targeted drug delivery would facilitate chemotherapeutic treatment of the neoplasms by minimizing systemic drug exposure (and hence potentially toxic systemic side effects) while simultaneously maximizing drug exposure to the neoplasms.
A method for such targeted drug delivery that has been researched and used extensively involves the use of vesicles sensitive to artificially generated factors such as ultrasound. However, vesicles sensitive to factors such as ultrasound are typically attendant with the inconvenience and cost associated with the use of external medical equipment, such as an ultrasound machine. Also, it is not always clear, such as in the case of metastatic tumors (where the tumors' precise locations may be unknown), where the factor (for example, ultrasound waves) should be directed.
Since the goal is to treat growth factor-overexpressing neoplasms, the ideal method for targeted drug delivery would involve the use of vesicles sensitive to abnormal (or excessive) amounts of growth factors (that is, growth factor sensitive vesicles). Such growth factor sensitive vesicles would be of great clinical significance because they could be used to specifically release chemotherapeutic agents in the neighborhood of growth factor-overexpressing neoplasms. However, due to the technical challenges inherent in creating a vesicle sensitive to growth factors, no such vesicles have previously been developed. The technical challenges in creating such a vesicle arise because, unlike factors such as ultrasound waves, growth factors do not have the ability to directly destabilize a vesicle.
As such, there is no relevant prior art pertaining to the growth factor sensitive vesicle of the invention.
3. Objects and Advantages
Accordingly, several objects and advantages of the invention are:                (a) to provide a growth factor sensitive vesicle which can carry and deliver a wide variety of chemotherapeutic and other pharmaceutical agents;        (b) to provide a growth factor sensitive vesicle which can be easily manufactured in a wide variety of external and internal dimensions;        (c) to provide a growth factor sensitive vesicle which can have a wide variety of vesicle compositions;        (d) to provide a growth factor sensitive vesicle which can have a wide variety of vesicle surface modifications; and        (e) to provide a growth factor sensitive vesicle which can simultaneously be sensitive to other factors, such as ultrasound.        
Further objects and advantages will become apparent from a consideration of the ensuing description and drawings.